The birth of galaxies
This is an artist's impression of the early formative years of our Milky Way galaxy, about 12.7 thousand million years ago. That long ago, the majestic spiral arms of our galaxy had not yet formed; the sky was a sea of globular star clusters.
A watercolour fantasyland? No. It's actually a photograph of the centre of the Swan Nebula, or M17, a hotbed of newly born stars wrapped in colourful blankets of glowing gas and cradled in an enormous cold, dark hydrogen cloud. This stunning picture was taken by the newly installed Advanced Camera for Surveys (ACS) aboard the NASA/ESA Hubble Space Telescope.
The region of the nebula shown in this picture is about 3500 times wider than our Solar System. The area also represents about 60 percent of the total view captured by ACS. The nebula resides 5500 light-years away in the constellation Sagittarius.